The cost of poured concrete construction is currently high because of the cost of material, such as multiple heavy wooden uprights, braces and ties which are required to support the forms and maintain accurate spacing between them and because of the labor cost incurred in constructing and removing these supports. Cost is further increased by the fact that access to one side of the form is often difficult or impossible to achieve. If the concrete is to be poured below ground level the excavation must be widened by several feet to provide the space necessary to build the outside supporting structure, and after the structure is removed the additional space must be backfilled. If the concrete is to be poured more than a few feet above ground, construction of the necessary supporting structure on the outside of the building and its subsequent removal may be vary costly and dangerous to workmen.
Concrete form tie rods or clamps of various types are well known in the prior art. Insertion, or installation and removal of the prior art clamps conventionally require access to both sides of the form. An example of such prior art structures is disclosed in U.S. Pat. No. 2,320,869. The clamp assembly of the present invention can be installed and removed from one side of the form. Except for the spacer member, which is left imbedded in the poured concrete, the clamp may be withdrawn and reused. The clamp assembly is simply constructed but, used at spaced intervals over the form, the two sides of the form are rigidly held in place in three dimensions with a precisely determined space between the sides of the form.